MODULATION OF MONOCARBOXYLIC ACID TRANSPORTERS IN BRAIN

脑中单羧酸转运蛋白的调节

• 批准号: 6637680
• 负责人: LESTER Richard DREWES
• 金额: $ 29.85万
• 依托单位: UNIVERSITY OF MINNESOTA DULUTH
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 2005-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6637680
• 关键词: animal genetic material tag; astrocytes; brain metabolism; carboxylate; cerebellum; cerebral cortex; cerebral ischemia /hypoxia; gene induction /repression; hippocampus; immunocytochemistry; laboratory rat; lactic acidosis; membrane transport proteins; neurogenetics; neurons; nutrition related tag

DESCRIPTION: Lactate and related monocarboxylic acids are important substrates and metabolic products of brain metabolism. Under conditions such as starvation, high fat consumption, and early development (newborn or suckling neonates), monocarboxylates such as lactate, pyruvate and ketone bodies may be extracted from the blood and used by the brain as fuels. Recent evidence suggests metabolic coupling occurs between astrocytes and neurons whereby lactate produced by astrocytes is utilized by neurons during neural activation. The overall objective of this proposal is to characterize the monocarboxylic acid transporters in brain and their role in blood-brain transport and cerebral metabolism. This includes molecular identification of the membrane proteins responsible for transporting monocarboxylic acids (lactic, pyruvic, acetoacetic and ^D- hydroxybutyric acids) across the plasma membranes of endothelial cells, astrocytes, and neurons; characterization of their cellular location, expression, regulation, and role in cerebral metabolism. The principal hypotheses to be tested are that: 1) the requisite monocarboxylate transporters (MCTs) for metabolic coupling between astrocytes and neurons are present in rat brain cortex, hippocampus and cerebellum; 2) upregulation of at least two separate MCT genes (MCT1 and MCT2) occurs independently (spatially and temporally) during postnatal development; 3) animals with elevated expression of brain MCTs from dietary manipulations are more resistant to hypoxic/ischemic cell damage than control animals; and 4) brain lactic acidosis associated with hypoxia/ischemia induces increased expression of MCTs. Specific antibodies and oligonucleotide probes for MCT1 and MCT2 will be used to analyze and quantify transporter proteins and mRNA. mRNA will be determined by ribonuclease protection assays and by in situ hybridization. MCT proteins will be determined by immunoblot detection and light and electron immunocytochemistry. The expression of MCTs in response to dietary alterations and global forebrain ischemia will be examined. Animals with experimentally increased levels of MCTs will be assessed for their ability to resist neurological damage following global forebrain ischemia. The genomic sequence of MCT1 and MCT2 will be closed and characterized and other brain MCTs will be identified. These proposed studies will contribute to a better understanding of the metabolic interrelationships among cells of the brain and therefore may lead to improved therapies, or preventive measures for patients with stroke or neurodegenerative disorders.

描述：乳酸和相关的一元羧酸是重要的 脑代谢的底物和代谢产物。 条件下 例如饥饿、高脂肪消耗和早期发育（新生儿或 哺乳新生儿）、单羧酸盐如乳酸盐、丙酮酸盐和酮 身体可以从血液中提取出来，并被大脑用作燃料。 最近的证据表明，代谢偶联发生在星形胶质细胞和 神经元，其中星形胶质细胞产生的乳酸被神经元利用， 神经激活 本建议的总体目标是 表征脑中的单羧酸转运蛋白及其在 血脑转运和脑代谢。 其中包括分子 负责转运的膜蛋白的鉴定 一元羧酸（乳酸、乳酸、乙酰乙酸和β-D-羟基丁酸 酸）穿过内皮细胞、星形胶质细胞的质膜， 神经元;它们的细胞位置，表达， 调节和在脑代谢中的作用。 主要假设是 测试的是：1）用于以下的必需的单羧酸转运蛋白（MCT）： 大鼠脑内存在星形胶质细胞和神经元之间的代谢偶联 皮质、海马和小脑; 2）上调至少两个单独的 MCT基因（MCT 1和MCT 2）独立发生（空间和时间） 在出生后发育期间; 3）脑表达升高的动物 来自饮食操作的MCT对缺氧/缺血细胞的抗性更强 损害比对照组动物;和4）脑乳酸酸中毒相关 缺氧/缺血诱导MCT表达增加。 特异性抗体 MCT 1和MCT 2的寡核苷酸探针将用于分析和 定量转运蛋白和mRNA。 mRNA将通过以下方式确定： 核糖核酸酶保护测定和原位杂交。 MCT蛋白 将通过免疫印迹检测以及光和电子 免疫细胞化学 MCTs的表达对饮食的反应 将检查改变和全前脑缺血。 动物 实验性增加的MCT水平将评估其能力， 以抵抗全前脑缺血后的神经损伤。 的 MCT 1和MCT 2的基因组序列将被封闭和表征， 将识别脑MCT。 这些拟议的研究将有助于 更好地了解代谢细胞之间的相互关系， 大脑，因此可能导致 改善中风患者的治疗或预防措施， 神经退行性疾病